History Brief
During the early summer of 1935 the Imperial Japanese Army issued requests to Mitsubishi, Kawasaki and Nakajima to competitively build advanced fighter aircraft prototypes to replace the Kawasaki Ki-10 fighter biplane. Before the end of 1935 Nakajima responded with the Ki-27, a single-seat monoplane fighter derived from the company's ‘Type P.E.’ aircraft.
Of the three contenders Nakajima’s nimble Ki-27 was by far more maneuverable than the other two but was not as fast and had a slower climb rate than the Kawasaki. Finally, after further testing in late 1937 the Nakajima was ordered into production as the Army’s Type 97 Fighter Model A or Ki-27A. Later production aircraft introduced further refinements, including an improved cockpit canopy, these carried the designation Ki-27B.